Aromatic amine derivative and organic electroluminescence device using the same

ABSTRACT

A aromatic amine derivative having an specific structure having a diphenyl amino group, and two or more of substituent bonding to benzene ring thereof, and in an organic electroluminescence device which comprises at least one organic thin film layer comprising a light emitting layer sandwiched between a pair of electrode consisting of an anode and a cathode, at least one of the organic thin film layer comprises the aromatic amine derivative singly or a component for a mixture thereof. The organic electroluminescence device exhibiting a long lifetime and high current efficiency as well as emitting blue light with high color purity, and also the aromatic amine derivative for realizing the organic EL device are provided.

REFERENCE TO PRIOR APPLICATIONS

This application is a Continuation application of U.S. Ser. No.11/336,855, filed Jan. 23, 2006; and claims priority to Japan patentapplication 2005-073474, filed Mar. 15, 2005, both incorporated hereinby reference.

TECHNICAL FIELD

The present invention relates to an aromatic amine derivative and anorganic electroluminescence (“electroluminescence” will be occasionallyreferred to as “EL”, hereinafter) device using the aromatic aminederivative, in particular, to an organic electroluminescence devicehaving a long lifetime, exhibiting high current efficiency and emittinga blue light with high color purity, and also to the aromatic aminederivative for realizing the organic EL device.

BACKGROUND ART

Since an organic EL device employing organic materials has been expectedas an application for a display device based on a solid light emissionhaving a popular price and a large viewing surface, substantialdevelopment have been conducted.

An organic EL device is constructed generally from a light emittinglayer and a pair of counter electrodes which sandwiches the layer. Alight emission is a phenomenon as follows; when an electric field isapplied between the electrodes, electrons are injected from the cathodeside and holes are injected from the anode side. Further, the electronsrecombine with the holes in the light emitting layer to produce itsexcitation state, and the energy from the excitation state is releasedas a light on returning to the ground state. The conventional organic ELdevices required a higher driving voltage and had lower luminance andcurrent efficiency in comparison with inorganic light emission diodes.In addition, the devices have not yet been put to practical use due tonotable deterioration of properties thereof.

Although current organic EL devices have been improved by inches, longerlifetime as well as higher current efficiency has been desired. Forexample, the technology employed the individual mono-anthracenecompounds as an organic light emission material has been disclosed(Patent literature 1). However, it has provided with the organic ELdevices having for example, only the luminance of 1650 cd/m² at theluminance of 165 mA/cm², and also the current efficiency is extremelylow so as to put them in practical use.

Further, the technology employing the individual bisanthracene compoundsas an organic light emission material has been disclosed (Patentliterature 2). However, it has provided with an organic EL device havingthe low current efficiency such as 1 to 3 cd/A, therefore furtherimprovement has been required so as to put in practical use.

Meanwhile, the organic EL device with a long lifetime, which employedthe distyryl compound added by styryl amine or so forth as an organiclight emitting material, has been proposed (Patent literature). However,the device has been required to improve its inadequate lifetime further.In addition, the technology employing the organic light emitting mediumlayer of the monoanthracene compounds or the bisanthracene compounds,and the distyryl compounds has been disclosed (Patent literature 4).However, it has provided with worsened color purity since the emissionspectrum become long wavelength due to the conjugated structure of thestyryl compounds.

Further, the devices emitting blue light employed the diaminochrysenederivatives have been disclosed in Patent literature 5. However, thedevice has been required to improve its inadequate lifetime in spite ofits excellent current efficiency.

Patent literature 1: Japanese Patent Application Laid-open No. Heisei 11(1999)-3782, Patent literature 2: Japanese Patent Application Laid-openNo. Heisei 8 (1996)-12600, Patent literature 3: International PCTpublication No. WO 094/006157, Patent literature 4: Japanese PatentApplication Laid-open No. 2001-284050, Patent literature 5:International PCT publication No. WO 04/044088.

DISCLOSURE OF THE INVENTION

The present invention has been made to overcome the above problems andhas an objective of providing an organic electroluminescence devicehaving a long lifetime, exhibiting the high current efficiency andemitting blue light with high color purity, and also providing anaromatic amine derivative for realizing the organic EL device.

As a results of intensive researches and studies to provide with anaromatic amine derivative having the above preferred properties and withan organic EL device employing the derivative, it has been found thatthe objective can be accomplished by employing the aromatic aminoderivative represented by the general formula (1). The derivativecontains a diphenyl amino group and two or more of substituents bondedto benzene ring thereof. Such being the case, the present invention hasbeen accomplished on the basis of the foregoing findings andinformation.

Namely, the present invention is to provide the aromatic aminederivative represented by the following general formula (1).

In the general formula (1), A₁ to A₄ each independently represents ahydrogen atom, a substituted or unsubstituted alkyl group having carbonatoms of 1 to 50, a substituted or unsubstituted aryl group having ringcarbon atoms of 5 to 50, a substituted or unsubstituted aralkyl grouphaving ring carbon atoms of 6 to 50, a substituted or unsubstitutedcycloalkyl group having ring carbon atoms of 3 to 50, a substituted orunsubstituted alkoxyl group having ring carbon atoms of 1 to 50, asubstituted or unsubstituted aryloxy group having ring carbon atoms of 5to 50, a substituted or unsubstituted arylamino group having ring carbonatoms of 5 to 50, a substituted or unsubstituted alkylamino group havingcarbon atoms of 1 to 20, a substituted or unsubstituted hetero ringgroup having ring carbon atoms of 5 to 50 or a halogen atom. a, b, c andd each independently represents an integer of 0 to 3.

When a, b, c and d each is two or more, A₁ to A₄ are the same with ordifferent from each other.

A₅ to A₁₂ each independently represents a substituted or unsubstitutedalkyl group having carbon atoms of 1 to 50, a substituted orunsubstituted aryl group having ring carbon atoms of 5 to 50, asubstituted or unsubstituted aralkyl group having ring carbon atoms of 6to 50, a substituted or unsubstituted cycloalkyl group having ringcarbon atoms of 3 to 50, a substituted or unsubstituted alkoxyl grouphaving ring carbon atoms of 1 to 50, a substituted or unsubstitutedaryloxy group having ring carbon atoms of 5 to 50, a substituted orunsubstituted arylamino group having ring carbon atoms of 5 to 50, asubstituted or unsubstituted alkylamino group having carbon atoms of 1to 20, a substituted or unsubstituted hetero ring group having ringcarbon atoms of 5 to 50 or a halogen atom. A₅ and A₆, A₇ and A₈, A₉ andA₁₀, and A₁₁ and A₁₂ may respectively bond each other to form asaturated or unsaturated ring.

R₁ to R₁₀ each independently represents a hydrogen atom, a substitutedor unsubstituted alkyl group having carbon atoms of 1 to 20, asubstituted or unsubstituted aryl group having ring carbon atoms of 5 to20, a substituted or unsubstituted aralkyl group having ring carbonatoms of 1 to 20, a substituted or unsubstituted cycloalkyl group havingring carbon atoms of 3 to 20.

Further, the present invention provides an organic EL device comprisingat least one of organic thin film layers including a light emittinglayer sandwiched between a pair of electrode consisting of an anode anda cathode, wherein a least one of the organic thin film layers containsthe aromatic amine derivative singly or as a component for a mixturethereof.

An organic EL device employing an aromatic amine derivative of thepresent invention exhibits adequate luminance of emitted light at lowdriving voltage and high current efficiency, and has a long lifetime dueto its difficult deterioration during a long time use.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows ¹H-NMR spectrum of the amine derivative obtained inSynthesis Example 1.

FIG. 2 shows ¹H-NMR spectrum of the amine derivative obtained inSynthesis Example 2.

FIG. 3 shows ¹H-NMR spectrum of the amine derivative obtained inSynthesis Example 3.

FIG. 4 shows ¹H-NMR spectrum of the amine derivative obtained inSynthesis Example 4.

THE PREFERRED EMBODIMENT TO CARRY OUT THE INVENTION

The aromatic amine derivative of the present invention is represented bythe following general formula (1):

The aromatic amine derivative represented by the general formula (1) isexplained as follows;

In the general formula (1), A₁ to A₄ each independently represents ahydrogen atom, a substituted or unsubstituted alkyl group having carbonatoms of 1 to 50, preferably 1 to 20, a substituted or unsubstitutedaryl group having ring carbon atoms of 5 to 50, preferably 5 to 20, asubstituted or unsubstituted aralkyl group having ring carbon atoms of 6to 50, preferably 6 to 20, a substituted or unsubstituted cycloalkylgroup having ring carbon atoms of 3 to 50, preferably 5 to 12, asubstituted or unsubstituted alkoxyl group having ring carbon atoms of 1to 50, preferably 1 to 6, a substituted or unsubstituted aryloxy grouphaving ring carbon atoms of 5 to 50, preferably 5 to 18, a substitutedor unsubstituted aryl amino group having ring carbon atoms of 5 to 50,preferably 5 to 18, a substituted or unsubstituted alkylamino grouphaving carbon atoms of 1 to 20, preferably 1 to 6, a substituted orunsubstituted hetero ring group having ring carbon atoms of 5 to 50,preferably 5 to 20 or a halogen atom.

A₅ to A₁₂ each independently represents a substituted or unsubstitutedalkyl group having carbon atoms of 1 to 50, preferably 1 to 20, asubstituted or unsubstituted aryl group having ring carbon atoms of 5 to50, preferably 5 to 20, a substituted or unsubstituted aralkyl grouphaving ring carbon atoms of 6 to 50, preferably 6 to 20, a substitutedor unsubstituted cycloalkyl group having ring carbon atoms of 3 to 50,preferably 5 to 12, a substituted or unsubstituted alkoxyl group havingring carbon atoms of 1 to 50, preferably 1 to 6, a substituted orunsubstituted aryloxy group having ring carbon atoms of 5 to 50,preferably 5 to 18, a substituted or unsubstituted arylamino grouphaving ring carbon atoms of 5 to 50, preferably 5 to 18, a substitutedor unsubstituted alkylamino group having carbon atoms of 1 to 20,preferably 1 to 6, a substituted or unsubstituted hetero ring grouphaving ring carbon atoms of 5 to 50, preferably 5 to 20 or a halogenatom.

An alkyl group for A₁ to A₁₂ includes, for example, methyl group, ethylgroup, propyl group, isopropyl group, butyl group, sec-butyl group,tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group,stearyl group, 2-phenyl isopropyl group, trichloromethyl group,trifluoromethyl group, benzyl group, α-phenoxybenzyl group,α,α-dimethylbenzyl group, α,α-methylphenylbenzyl group,α,α-ditrifluoromethylbenzyl group, triphenylmethyl group andα-benzyloxybenzyl group.

An aryl group of A₁ to A₁₂ includes, for example, phenyl group,2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group,4-ethylphenyl group, biphenyl group, 4-methlbiphenyl group,4-ethylbiphenyl group, 4-cyclohexylbiphenyl group, terphanyl group,3,5-dichlorophenyl group, naphthyl group, 5-methylnaphthyl group,anthryl group, pyrenyl group, chrysenyl group, fluororanthenyl group andperylenyl group.

An aralkyl group for A₁ to A₁₂ includes, for example, benzyl group,1-phenylethyl group, 2-phenylethyl group, 1-phenylisopropyl group,2-phenylisopropyl group, phenyl-t-butyl group, α-naphthylmethyl group,1-α-naphthylethyl group, 2-α-naphthylethyl group, 1-α-naphthylisopropylgroup, 2-α-naphthylisopropyl group, β-naphthylmethyl group,1-β-naphthylethyl group, 2-β-naphthylethyl group, 1-β-naphthylisopropylgroup, 2-β-naphthylisopropyl group, 1-pyrrolylmethyl group,2-(1-pyrrolyl)ethyl group, p-methylbenzyl group, m-methylbenzyl group,o-methylbenzyl group, p-chlorobenzyl group, m-chlorobenzyl group,o-chlorobenzyl group, p-bromobenzyl group, m-bromobenzyl group,o-bromobenzyl group, p-iodeben-5-zyl group, p-iodobenzyl group,m-iodobenzyl group, o-iodobenzyl group, p-hydroxybenzyl group,m-hydroxybenzyl group, o-hydroxybenzyl group, p-aminobenzyl group,m-aminobenzyl group, o-aminobenzyl group, p-nitrobenzyl group,m-nitrobenzyl group, o-nitrobenzyl group, p-cyanobenzyl group,m-cyanobenzyl group, o-cyanobenzyl group, 1-hydroxy-2-phenylisopropylgroup, 1-chloro-2-phenylisopropyl group and the like.

A cycloalkyl group for A₁ to A₁₂ includes, for example, cyclopropylgroup, cyclobutyl group, cyclopentyl group, cyclohexyl group,cycloheptyl group, cyclooctyl group, cyclononyl group, bicycloheptylgroup, bicyclooctyl group, tricycloheptyl group and adamantyl group.Cyclopentyl group, cyclohexyl group, cycloheptyl group, bicycloheptylgroup, bicyclooctyl group and adamantyl group are preferable. An alkoxygroup for A₁ to A₁₂ includes, for example, methoxy group, ethoxy group,propoxy group, isopropoxy group, butoxy group, isobutoxy group,sec-butoxy group, tert-butoxy group, various pentyloxy groups andvarious hexyloxy groups. An aryloxy group for A₁ to A₁₂ includes, forexample, pheoxy group, tilyloxy group and naphtyloxy group.

An arylamino group for A₁ to A₁₂ includes, for example, diphenylaminogroup, ditolylamino group, dinaphthylamino group and naphthylphenylaminogroup. An alkylamino group for A₁ to A₁₂ includes, for example,dimethylamino group, diethylamino group and dihexylamino group. A heteroring group for A₁ to A₁₂ includes a moiety of, for example, imidazole,benzoimidazole, pyrrole, furan, thiophene, benzothophene, oxadiazoline,indoline, carbazol, pyridine, quinoline, isoquinoline, benzoquinone,pyrazine, imidazolidine and piperidine. A halogen atom for A₁ to A₁₂includes, for example, a fluorine atom, a chlorine atom and a bromineatom.

In the general formula (1), a to d each independently represents aninteger of 0 to 3, preferably 0 to 1.

When a to d each is two or more, A₁ to A₄ are the same with or differentfrom each other and also may bond each other to form a saturated orunsaturated ring.

In addition, A₅ and A₆, A₇ and A₈, A₉ and A₁₀, and A₁₁ and A₁₂ mayrespectively bond each other to form a saturated or unsaturated ring.

The above ring includes, for example, cycloalkane having carbon atoms of4 to 12 such as cyclobutane, cyclopentane, cyclohexane adamantane, andnorbornane, cycloalkene having carbon atoms of 4 to 12 such ascyclobutene, cyclopentene, cyclohexene, cycloheptene and cyclooctene,cycloalkadiene having carbon atoms of 6 to 12 such as cylohexadiene,cycloheptadiene and cyclooctadiene, an aromatic ring having ring carbonatoms of 6 to 50 such as benzene, naphthalene, phenanthrene, anthracene,pyrene, chrysene and acenaphthylene, and a hetero ring having ringcarbon atoms of 5 to 50 such as imidazole, pyrrole, furan, thiophene andpyridine.

In the general formula (1), R₁ to R₁₀ each independently represents ahydrogen atom, a substituted or unsubstituted alkyl group having carbonatoms of 1 to 20, a substituted or unsubstituted aryl group havingcarbon atoms of 5 to 20, a substituted or unsubstituted aralkyl grouphaving carbon atoms of 1 to 20 or a substituted or unsubstitutedcycloalkyl group having carbon atoms of 3 to 20.

An example for the above each group includes the groups, of which thecarbon atom number fits to those of the groups among the groups shownfor A₁ to A₁₂.

A substituent for A₁ to A₁₂ and R₁ to R₁₀ above includes a substitutedor unsubstituted aryl group having ring carbon atoms of 5 to 50, asubstituted or unsubstituted alkyl group having carbon atoms of 1 to 50,a substituted or unsubstituted alkoxy group having carbon atoms of 1 to50, a substituted or unsubstituted aralkyl group having carbon atoms of6 to 50, a substituted or unsubstituted aryloxy group having ring carbonatoms of 5 to 50, a substituted or unsubstituted arylthio group havingring carbon atoms of 5 to 50, a substituted or unsubstitutedalkoxycarbonyl group having carbon atoms of 1 to 50, an amino group, ahalogen atom, a cyano group, a hydroxyl group and carboxyl group.

Among those, an alkyl group having carbon atoms of 1 to 10, a cycloalkylgroup having carbon atoms of 5 to 7, a alkoxy group having carbon atomof 1 to 10 and a cycloalkyl group having carbon atoms of 5 to 7 arepreferable, and methyl group, ethyl group, n-propyl group, isopropylgroup, n-butyl group, sec-butyl group, tert-butyl group, n-pentyl group,n-hexyl group, cyclopentyl group and cyclohexyl group are particularlypreferable.

As an aromatic amine derivative of the present invention represented bythe general formula (1), a structure represented by the followinggeneral formula (2) is preferable; the formula (2) means that R₁ to R₁₀are hydrogen atoms in the general formula (1).

Further, in the general formulae (1) and (2), it is preferable that A₅to A₁₂ each independently represents a substituted or unsubstitutedalkyl group having carbon toms of 1 to 50, and it is particularlypreferable that A₁ to A₁₂ each independently represents a substituted orunsubstituted alkyl group having carbon atoms of 1 to 50.

The specific examples of the aromatic amine derivatives represented bythe general formulae (1) and (2) include the following, but not limitedthereto;

Among those, Compound (D-1), (D-2), (D-5), (D-6), (D-9), (D-17), (D-18),(D-20), (D-21), (D-22), (D-23), (D-25) and (D-26) are particularlypreferable.

The following explains a process for manufacturing the aromatic aminederivatives of the present invention.

The process is not limited for producing the aromatic amine representedby the general formula (1), therefore, a well known process can beapplied; for example, 6,12-dibromochrysene is aminated with diarylamineso as to produce the aromatic amine derivative by applying the processdescribed in Rev. Roum. Chim., 341907 (1989), M. D. Bancia et al.

The aromatic amine derivative represented by the general formula (1)comprises a diaminochrysene structure which is a center for lightemission and is bonded with a substituted benzene ring. Therefore,association between the derivatives is avoidable and a longer lifetimeis exhibited. When the above substituent is two or more, associationbetween the derivatives is more avoidable and a further longer lifetimeis exhibited. In addition, the derivative exhibits strong fluorescenceat a solid state, excellent light emission and fluorescence quantumefficiency of 0.3 or larger. Further, since it has a splendid holeinjecting capability and a hole transportation capability from a metalelectrode or an organic thin film layer, and also electron injectingcapability and electron transportation capability from a metal electrodeor an organic thin film layer, it can be used for a light emittingmaterial of an organic EL device, particularly for a effective dopingmaterial. In addition, other hole transportation material, electrontransportation material or doping material may be used.

The organic EL device of the present invention means a device comprisingat least one organic thin film layer formed between an anode and acathode. In the case based on a single layer, a light emitting layer isprovided between an anode and a cathode. A light emitting layer containsa light emitting material and also may contain a hole injecting materialor an electron injecting material so as to transport holes injected fromthe anode or electrons injected from the cathode.

Since the aromatic amine derivative exhibits high light emissioncapability and has splendid hole injecting capability/holetransportation capability and also electron injectingcapability/electron transportation capability, it can be used for alight emitting layer as a light emitting material or a doping material.In the organic EL device of the present invention, it is preferable thata light emitting layer contains the organic amine derivative, and thecontent thereof is generally 0.1 to 20% by weight, more preferably 1 to10% by weight.

Further, since the aromatic amine derivative exhibits high holetransportation capability and electron transportation capability as wellas extremely high fluorescence quantum efficiency, and also can beformed into a uniform film, a light emitting layer may be formed byitself. In addition, in an organic EL device of the present inventioncomprising at least two of organic thin film layers including a lightemitting layer sandwiched between a pair of electrode consisting of ananode and a cathode, it is preferable that an organic layer comprisingthe aromatic amine derivative as the main component thereof is placedbetween the anode and the cathode. The organic layer includes a holeinjecting layer, a hole transporting layer and so forth.

More further, when the aromatic amine derivative is contained as adoping material, it is preferable that at least a derivative selectedfrom anthracene derivatives represented by the general formulae (3) and(4), and a pyrene derivative represented by the general formula (5) iscontained as a host material.

In the general formula (3), X₁ and X₂ each independently represents ahydrogen atom, a substituted or unsubstituted alkyl group having carbonatoms of 1 to 50, a substituted or unsubstituted aryl group having ringcarbon atoms of 5 to 50, a substituted or unsubstituted aralkyl grouphaving ring carbon atoms of 6 to 50, a substituted or unsubstitutedcycloalkyl group having ring carbon atoms of 3 to 50, a substituted orunsubstituted alkoxyl group having ring carbon atoms of 1 to 50, asubstituted or unsubstituted aryloxy group having ring carbon atoms of 5to 50, a substituted or unsubstituted arylamino group having ring carbonatoms of 5 to 50, a substituted or unsubstituted alkylamino group havingcarbon atoms of 1 to 20, a substituted or unsubstituted hetero ringgroup having ring carbon atoms of 5 to 50 or a halogen atom. e and feach independently represents an integer of 0 to 4. When e and f are twoor more, X₁ and X₂ may be the same with or different from each other.

Ar₁ and Ar₂ each independently represents a substituted or unsubstitutedaryl group having ring carbon atoms of 5 to 50, a substituted orunsubstituted hetero ring group having ring carbon atoms of 5 to 50, andat least one of Ar₁ and Ar₂ represents a substituted or unsubstitutedaryl group containing a hetero ring having ring carbon atoms of 10 to50. m represents an integer of 1 to 3. When m is 2 or more, the groupsin [ ] may be the same with or different from each other.

The specific examples of each group and substituent of X₁ and X₂, and,Ar₁ and Ar₂ are similar to the ones shown in the general formula (1).

In the general formula (4), X₁ to X₃ each independently representshydrogen atom, a substituted or unsubstituted alkyl group having carbonatoms of 1 to 50, a substituted or unsubstituted aryl group having ringcarbon atoms of 5 to 50, a substituted or unsubstituted aralkyl grouphaving ring carbon atoms of 6 to 50, a substituted or unsubstitutedcycloalkyl group having ring carbon atoms of 3 to 50, a substituted orunsubstituted alkoxyl group having ring carbon atoms of 1 to 50, asubstituted or unsubstituted aryloxy group having ring carbon atoms of 5to 50, a substituted or unsubstituted arylamino group having ring carbonatoms of 5 to 50, a substituted or unsubstituted alkylamino group havingcarbon atoms of 1 to 20, a substituted or unsubstituted hetero ringgroup having ring carbon atoms of 5 to 50 or a halogen atom. e, f and geach independently represents an integer of 0 to 4. When e, f and g aretwo or more, X₁, X₂ and X₃ are the same with or different from eachother. Ar₁ represents a substituted or unsubstituted aryl groupcontaining a condensed ring having ring carbon atoms of 10 to 50, andAr₃ represents a substituted or unsubstituted aryl group having ringcarbon atoms of 5 to 50. n represents an integer of 1 to 3. When n is 2or more, the groups in [ ] may be the same with or different from eachother. The specific examples of each group and substituent of X₁, X₂,X₃, Ar₁ and Ar₃ are similar to the ones shown in the general formula(1).

The specific examples of anthracene derivatives represented by thegeneral formulae (3) and (4) include the following, but not limitedthereto;

Ar₅ and Ar₆ in the general formula (5) each independently represents asubstituted or unsubstituted aryl group having ring carbon atoms of 6 to50. L₁ and L₂ each independently represents a substituted orunsubstituted phenylene group, a substituted or unsubstitutednaphthalene group, a substituted or unsubstituted fluorenylene group ora substituted or unsubstituted dibenzosilolylene group,

s represents an integer of 0 to 2, p represents of an integer of 1 to 4,q represents an integer of 0 to 2 and r represents an integer of 0 to 4,

further, L₁ or Ar₅ bonds to any one of 1 to 5 position of pyrene, and L₂or Ar₆ bonds to any one of 6 to 10 position thereof, however, when p+ris an even number, Ar₅, Ar₆, L₁ and L₂ satisfy a following requirement(1) or a requirement (2):

(1) Ar₅≠Ar′₆ and/or L₁≠L₂, wherein ≠ means that each group has adifferent structure,

(2) when Ar₅=Ar₆ and L₁=L₂, (2-1) s≠q and/or p≠r, or (2-2) when s=q andp=r,

(2-2-1) both L₁ and L₂ or pyrene bond respectively to a differentposition of Ar₅ and Ar₆, or

(2-2-2) both L₁ and L₂ or pyrene bond respectively to the same positionof Ar₅ and Ar₆ excluding a case where both L₁ and L₂ or both Ar₅ and Ar₆bond respectively to 1 and 6, or 2 and 7 positions thereof.

The specific examples of each group and substituent of Ar₅, Ar₆, L₁, andL₂ are similar to the ones shown in the general formula (1).

The specific examples of the pyrene derivatives represented by thegeneral formula (5) include the following, but not limited thereto;

The organic EL device comprising the plural organic thin film layers ofthe present invention includes a laminated structure such as an anode/ahole injecting layer/a light emitting layer/a cathode, an anode/a lightemitting layer/an electron injecting layer/a cathode, and an anode/ahole injecting layer/a light emitting layer/an electron injectinglayer/a cathode. In addition to the aromatic amine derivatives, ifrequired, well known light emitting materials, doping materials, holeinjecting materials and electron injecting materials may be added intothe plural layers. By making the organic thin film layer into a plurallayer structure, it is possible to prevent luminance or lifetime of anorganic EL device from decreasing due to quenching. If required, a lightemitting material, a doping material, a hole injecting material or anelectron injecting material may be used as a combination thereof. Inaddition, it is also possible to improve emission luminance or currentefficiency, and obtain red light emission or blue light emission.Further, a hole injecting layer, a light emitting layer and an electroninjecting layer each may be formed into a layer structure having two ormore layers. In the case of a hole injecting layer, a layer, into whichholes are injected from an electrode, is called as a hole injectionlayer, and a layer, which receives holes for a hole injecting layer andtransports them to a light emitting layer, is called as a holetransporting layer.

Correspondingly, in the case of an electron injecting layer, a layer,into which electrons are injected from an electrode, is called as anelectron injection layer, and a layer, which receives electrons from anelectron injecting layer and transports them to a light emitting layer,is called as an electron transporting layer. Above each layer isselected and applied based on a factor such as energy level and heatresistance of materials, and degree of adhesion to an organic layer oran metal electrode.

A host material or a dopant other than the aforementioned generalformulae (3) to (5) being able to be used together with the aromaticamine derivatives includes, condensed multiaromatic compounds andderivatives thereof such as naphthalene, phenanthrene, rubrene,anthracene, tetracene, pyrene, perylene, chrysene, decacyclene,coronene, tetraphenylcyclopentadiene, pentaphenylcyclopentadiene,fluorene, spirofluorene, 9,10-diphenylanthracene,9,10-bis(phenylethinyl)anthracene and 1,4-bis(9′-ethinylanthracene)benzene, an organic metal complexes such as tris(8-quinolinnolate)aluminium, bis-(2-methyl-8-quinolinolate)-4-(phenylphenolinate)aluminum, a triarylamine derivative, a styryl amine derivative, astilbene derivative, a coumarin derivative, a pyran derivative, anoxazone derivative, a benzothiazole derivative, a benzoxazolederivative, a benzoimidazole derivative, a pyrazine derivative, acinnamic acid ester derivative, a diketonepyrrolopyrrole derivative, anacridone derivative and a quinacridone derivative, but not limitedthereto.

It is preferable for a hole injecting material that a compound exhibitshole transportation capability, a hole injection effect from an anode, asplendid hole injection effect to a light emitting layer or a lightemitting material, prevents exciton generated in a light emitting layerfrom transporting to an electron injecting layer or an electroninjecting layer, and has excellent capability of forming a thin film.Specific examples thereof include a phthalocyanine derivative, anaphthalocyanine derivative, a porphyrin derivative, oxazole,oxadiazole, triazole, imidazole, imidazolone, imidazolethion,pyrazoline, pyrazolone, tetrahydroimidazole, oxazole, oxadiazole,hydrazone, acylhydrazone, polyarylalkane, stilbene, butadiene, benzidinebased triphenyl amine, styrylamine based triphenyl amine, diamine basedtriphenylamine and the like, and their derivatives, and also polymermaterials such as polyvinylcarbazole, polysilane and electroconductivepolymer, but not limited thereto.

More effective hole injecting material includes a aromatic tertiaryamine derivative and a phthalocyanine derivative among hole injectingmaterials usable for the organic EL device.

The tertiary amine derivative includes, for example, triphenylamine,tritolylamine, tridiphenylamine,N,N′-diphenyl-N,N′-(3-methylphenyl)-1,1′biphenyl-4,4′-diamine,N,N,N′,N′-(4-methylphenyl)-1,1′-phenyl-4,4′-diamine,N,N,N′,N′-(4-methylphenyl)-1,1′-biphenyl-4,4′-diamine,N,N′-diphenyl-N,N′-dinaphthyl-1,1′-biphenyl-4,4′-diamine,N,N′-dinaphenyl-N,N′-dinaphthyl-1,1′-biphenyl-4,4′-diamine,N,N′-(methylphenyl)-N,N-(4-n-butylphenyl)-phenanthrene-9,10-diamine,N,N-bis(4-di-4-tolylaminephenyl)-4-phenyl-cyclohexane, or oligomer orpolymer having a backbone of these aromatic tertiary-amines, but notlimited thereto.

Phthalocyanine (Pc) derivatives include, for example, phthalocyaninederivatives such as H₂Pc, CuPc, CoPc, NiPc, ZnPc, PdPc, FePc, MnPc,ClAlPc, ClGaPc, ClInPc, ClSnPc, Cl₂SiPc, (HO)AlPc, (HO)GaPc, VOPc,TiOPc, MoOPc, GaPc-O—GaPc and naphthalocyanine derivatives, but notlimited thereto. Further, it is preferable that the organic EL device ofthe present invention contains a layer such as the hole transportationlayer or the hole injecting layer, which comprises the aromatic tertiaryamine derivatives and/or the phthalocyanine derivatives, for example.The layer is formed between the light emitting layer and the anode.

It is preferable for an electron injecting material that a compoundexhibits electron transportation capability, an electron injectioneffect from a cathode, a splendid electron injection effect to a lightemitting layer or a light emitting material, prevents exciton generatedin a light emitting layer from transporting to a hole injecting layer,and has a excellent capability of forming a thin film. Specific examplesthereof include fluorene, anthraquinodimethane, diphenoquinone,thiopyrandioxide, oxazole, oxadiazole, triazole, imidazole,perylenetetracarboxylic acid, fluorenylidenmethane,anthraquinodimethane, anthrone and derivetives thereof, but not limitedthereto.

In addition, it is possible to increase desensitization by adding anelectron receptible substance into a hole injecting material and byadding an electron donating substance into an electron injectingmaterial.

An effective electron injecting material for the organic EL deviceincludes a metal complex compound and a 5 member ring derivative havinga nitrogen atom. The metal complex compound includes, for example,8-hydroxyquinolinate lithium, bis(8-hydroxyquinolinate) zinc,bis(8-hydroxyquinolinate) copper, bis(8-hydroxyquinolinate) manganese,tris(8-hydroxyquinolinate) aluminum, tris(2-methyl-8-hydroxyquinolinate)aluminum, tris(8-hydroxyquinolinate)gallium,bis(10-hydroxybenzo[h]quinolinate) beryllium,bis(10-hydroxybenzo[h]quinolinate) zinc,bis(2-methyl-8-hydroxyquinolinate) chlorogallium,bis(2-methyl-8-quinolinate)(o-cresolate) gallium,bis(2-methyl-8-quinolinate)(1-naphtholate) aluminum,bis(2-methyl-8-quinolinate)(2-naphtholate) gallium and the like, but notlimited thereto.

The 5 member ring derivative having a nitrogen atom includes, forexample, derivatives of oxazole, thiazole, oxadiazole, thiadiazole andtriazole. Specific examples thereof include2,5-bis(1-phenyl)-1,3,4-oxazole, dimethylPOPOP,2,5-bis(1-phenyl)-1,3,4-thaizole, 2,5-bis(1-phenyl)-1,3,4-oxadiazole,2-(4′-ter-butylphenyl)-5-bis(4″-biphenyl)-1,3,4-oxadiazole,2,5-bis(1-naphthyl)-1,3,4-oxadiazole,1,4-bis[2-(5-phenyloxadiazolyl)]benzen,1,4-bis[2-(5-phenyloxadiazolyl)-4-tert-butylbenzen],2-(4′-tert-butylphenyl)-5-(4″-biphenyl)-1,3,4-thiadiazole,2,5-bis(1-naphthyl)-1,3,4-thiaziazole,1,4-bis[2-(5-phenylthiadiazolyl)]benzen,2-(4′-tert-butylphenyl)-5-(4″-biphenyl)-1,3,4-triazole,2,5-bis(1-naphtyl)-1,3,4-triazole,1,4-bis[2-(5-phenyltriazolyl)]benzene, but not limited thereto.

A light emitting layer of the organic EL device of the present inventionmay contain at least one selected from a light emission material, adoping material, a hole injecting material and an electron injectionmaterial in the same layer in addition to at least an aromatic aminederivative selected from the general formula (1). In addition, anorganic EL device obtained by the present invention may be provided witha protective layer on the surface thereof, or covered entirely bysilicon oil, resin and the like so as to improve the stability totemperature, moisture, atmosphere and so forth.

A preferable electroconductive material employed for an anode of theorganic EL device comprises a material having a work function largerthan 4 eV. Examples thereof include carbon, aluminum, vanadium, iron,cobalt, nickel, tungsten, silver, gold, platinum, vanadium and alloythereof, and also a metaloxide such as tin oxide to be used for an ITOsubstrate and indium oxide to be used for a NESA substrate, and furtherorganic conductive resin such as polythiophene and polythiol.

A preferable electroconductive material employed for a cathode of theorganic EL device comprises a material having a work function smallerthan 4 eV. Examples thereof include magnesium, calcium, tin, zinc,titanium, yttrium, lithium, ruthenium, manganese, aluminum, lithiumfluoride and alloy thereof, but not limited thereto.

Typical examples of the alloy include magnesium-silver alloy,magnesium-indium alloy and lithium-aluminum alloy, but not limitedthereto. The ratio of the alloy components may selected properly bycontrolling the temperature of deposition source, atmosphere, vacuumlevel and the like on deposition.

An anode and a cathode each may be formed by two or more layers ifrequired.

The organic EL device on the present invention can be preferablyprovided with at least a substantial transparent side; the transparentmeans transparent in wavelength zone of light emission. Further, asubstrate can be preferably transparent. A transparent electrode havingdesignated translucency is provided with a method such as vapordeposition, sputtering and the like by using the aforementionedconductive materials. An electrode of a light emitting surface haspreferably a light transmittance of 10% or greater. As a substratehaving mechanical and thermal strength, and transparency, glass sheetand transparent resin film are advantageously employed, but it shouldnot be construed as limiting it. Specific examples of the transparentresin film include resin film made of polyethylene ethylene-vinylacetate copolymer, ethylene-vinylalcohol copolymer, polypropyrene,polystyrene, polymethylmethacrylate, poluvinylchloride,polyvinylalcohol, polyvinylbutyral, nylon, polyether ether ketone,polysulfone, polyether sulfone,tetrafluoroethylene-perfluoroalkylvinylether copolymer,polyvinylfluoride, tetrafluoroethylene-ethylene copolymer,tetrafluoropropyrene-hexyluoropropyrene copolymer,polychlorotrifluoroethylene, polyvinylidenefluoride, polyesters,polycarbonate, polyurethene, polyimide, polyetherimide and the like.

The layers in the organic EL device of the present invention can beformed by any one of the dry film forming processes such as the vacuumvapor deposition process, the sputtering process, the plasma process,the ion plating process, or the wet film forming process such as thespin coating process, the dipping process and the flow coating process.The thickness of each layer of the organic thin film layers can beprovide with a reasonable thickness, but not particularly limited. Anexcessively thick layer requires a high applied voltage results indecreasing the current efficiency, and an excessively thin layer tendsto have defects such as pin holes. In general, the range from 5 nm to 10μm in thickness thereof is preferable, and the range from 10 nm to 0.2μm in thickness thereof is more preferable.

In the case of the wet film forming process, a film for each layer ismade of a material dissolved or dispersed in a appropriate solvent suchas ethanol, chloroform, tetrahydrofuran and dioxane, but not limitedthereto. In addition, in any one of the organic thin film layers, aappropriate resin or an additive may be used so as to improve filmforming capability, prevent from forming pin hole in the thin film andso forth. Examples of the employable resins include an insulating resinsuch as polystyrene, polycarbonate, polyarylate, polyester, polyamide,polyurethane, polysulfone, polymethylmethacrylate, polymethylacrylate,cellulose and copolymer thereof, a photoconductive resin such aspoly-N-vinylcarbazole and polysilane, and an electroconductive resinsuch as polythiophene and polypyrrole. Further, the additives include anantioxidant, ultraviolet absorbent, plasticizer and the like.

The organic EL device of the present invention can be used for a flatlight emitter of a flat panel display for a television hanging on walls,a backlight for a copying machine, a liquid crystal display, a lightsource for instruments, an indicator, a marker lamp and the like. Inaddition, the materials of the present invention may be used in thefields of a photo conductor of electrophotography, photoelectrictransfer devices, solar cells, image sensors and the like.

Example

This invention will be described in further detail with reference to theexamples.

Synthesis Example 1 Synthesis of Compound (D-1)

Under the atmosphere of argon gas, into a three neck flask of 300 mlequipped with a condenser, 3.8 g (10 mmol) of 6,12-dibromochrysene, 5.6g (25 mmol) of bis(3,5-dimethylphenyl)amine, 0.03 g (1.5 mol %) ofpalladium acetate, 0.06 g (3 mol %) of tri-t-butylphosphine, 2.4 g (25mmol) of t-sodiumbutoxide and 100 ml of dried toluene were placed, andthen stirred over night at 100 degC. After completion of the reaction,the crystal precipitated was separated by filtration, followed bywashing it with 50 ml of toluene and 100 ml of methanol, and then 6.2 gof pale yellow powder was obtained. It was confirmed that the productwas Compound (D-1) by the measurements of ¹H-NMR spectrum (FIG. 1) andFD-MS (Field Desorption Mass Spectrum). Yield: 92%. The measurement ofspectrum was conducted by DRX-500 made by Brucker Company (heavymethylene chloride solvent). In addition, the maximum absorption wavelength was 411 nm and the maximum fluorescent wavelength was 457 nm whenCompound obtained was measured in toluene solution.

Synthesis Example 2 Synthesis of Compound (D-2)

Under the atmosphere of argon gas, into a three neck flask of 300 mlequipped with a condenser, 3.8 g (10 mmol) of 6,12-dibromochrysene, 5.6g (25 mmol) of bis(3,4-dimethylphenyl)amine, 0.03 g (1.5 mol %) ofpalladium acetate, 0.06 g (3 mol %) of tri-t-butylphosphine, 2.4 g (25mmol) of t-sodiumbutoxide and 100 ml of dried toluene were placed, andthen stirred over night at 100 degC. After completion of the reaction,the crystal precipitated was separated by filtration, followed bywashing it with 50 ml of toluene and 100 ml of methanol, and then 6.6 gof pale yellow powder was obtained. It was confirmed that the productwas Compound (D-2) by the measurements of ¹H-NMR spectrum (FIG. 2) andFD-MS. Yield: 98%. In addition, the maximum absorption wave length was405 nm and the maximum fluorescent wavelength was 450 nm when Compoundobtained was measured in toluene solution.

Synthesis Example 3 Synthesis of Compound (D-9)

Under the atmosphere of argon gas, into a three neck flask of 300 mlequipped with a condenser, 3.8 g (10 mmol) of 6,12-dibromochrysene, 6.3g (25 mmol) of bis(3,4,5-trimethylphenyl)amine, 0.03 g (1.5 mol %) ofpalladium acetate, 0.06 g (3 mol %) of tri-t-butylphosphine, 2.4 g (25mmol) of t-sodiumbutoxide and 100 ml of dried toluene were placed, andthen stirred over night at 100 degC. After completion of the reaction,the crystal precipitated was separated by filtration, followed bywashing it with 50 ml of toluene and 100 ml of methanol, and then 7.1 gof pale yellow powder was obtained. It was confirmed that the productwas Compound (D-9) by the measurements of ¹H-NMR spectrum (FIG. 3) andFD-MS. Yield: 98%. In addition, the maximum absorption wave length was416 nm and the maximum fluorescent wavelength was 463 nm when Compoundobtained was measured in toluene solution.

Synthesis Example 4 Synthesis of Compound (D-23)

Under the atmosphere of argon gas, into a three neck flask of 300 mlequipped with a condenser, 3.8 g (10 mmol) of 6,12-dibromochrysene, 7.7g (25 mmol) of 3,5-dimethylphenyl-3′,5′-di-t-butylphenylamine, 0.03 g(1.5 mol %) of palladium acetate, 0.06 g (3 mol %) oftri-t-butylphosphine, 2.4 g (25 mmol) of t-sodiumbutoxide and 100 ml ofdried toluene were placed, and then stirred over night at 100 degC.After completion of the reaction, the crystal precipitated was separatedby filtration, followed by washing it with 50 ml of toluene and 100 mlof methanol, and then 7.6 g of pale yellow powder was obtained. It wasconfirmed that the product was Compound (D-23) by the measurements of¹H-NMR spectrum (FIG. 4) and FD-MS. Yield: 90%. In addition, the maximumabsorption wave length was 408 nm and the maximum fluorescent wavelengthwas 454 nm when Compound obtained was measured in toluene solution.

Example 1

A transparent electrode comprising indium-tin oxide having 120 nm offilm thickness was formed on a glass substrate of a 25 mm×75 mm×1.1 mmsize. The glass substrate was cleaned by application ultraviolet lightand ozone, and was place in a vacuum vapor deposition apparatus.

Firstly,N′,N″-bis[4-(diphenylamino)phenyl]-N′,N″-diphenylbiphenyl-,4′-diaminewas deposited to be 60 nm thickness as the hole injecting layer, andthen N,N,N′N′-tetrakis(4-biphenyl)-4,4′-benzidine was deposited thereonto be 20 nm as the hole transporting layer. Subsequently,10,10′-bis[1,1′, 4′, 1″]terphenyl-2-yl-9,9′-bianthracenyl(BTBAN) andCompound (D-1) as a doping material at a weight ratio of BTBAN:D1=40:2were deposited at once on the hole transporting layer to form the lightemitting layer having 40 nm thickness. Then tris (8-hydroxyquinolinate)aluminum was deposited to be 20 nm thicknesses. Further, lithiumfluoride was deposited to be 1 nm thickness and then aluminum wasdeposited to be 150 nm thicknesses. The aluminum/lithium fluorideperforms as the cathode. The organic EL device was prepared as statedabove.

The device was tested by passing electric current, a blue light emissionwith a current efficiency of 7.1 cd/A and an emission luminance of 710cd/m² (maximum light emission wavelength: 466 nm) was observed at avoltage of 6.5 V and a current density of 10 mA/cm2. It was continuouslytested by passing electric current at an initial luminance of 500 cd/m²,the half lifetime was founded to be 16,000 hours.

Example 2

The organic EL device was fabricated similarly as Example 1 except thatCompound (D-5) was used in place of Compound (D-1). The device wastested by passing electric current, a blue light emission with a currentefficiency of 7.8 cd/A and an emission luminance of 780 cd/m² (maximumlight emission wavelength: 468 nm) was observed at a voltage of 6.5 Vand a current density of 10 mA/cm2. It was continuously tested bypassing electric current at an initial luminance of 500 cd/m², the halflifetime was founded to be 20,000 hours or more.

Example 3

The organic EL device was fabricated similarly as Example 1 except thatCompound (D-9) was used in place of Compound (D-1). The device wastested by passing electric current, a blue light emission with a currentefficiency of 8.6 cd/A and an emission luminance of 860 cd/m² (maximumlight emission wavelength: 471 nm) was observed at a voltage of 6.5 Vand a current density of 10 mA/cm². It was continuously tested bypassing electric current at an initial luminance of 500 cd/m², the halflifetime was founded to be 20,000 hours or more.

Example 4

The organic EL device was fabricated similarly as Example 1 except that10-(3-(naphthalene-1-yl)phenyl)-9-(naphthalene-2-yl) anthracene in placeof BTBAN was used as the host material. The device was tested by passingelectric current, a blue light emission with a current efficiency of 8.0cd/A and an emission luminance of 799 cd/m² (maximum light emissionwavelength: 469 nm) was observed at a voltage of 6.5 V and a currentdensity of 10 mA/cm². It was continuously tested by passing electriccurrent at an initial luminance of 500 cd/m², the half lifetime wasfounded to be 20,000 hours or more.

Example 5

The organic EL device was fabricated similarly as Example 2 except that1-(9,9-dimethyl-2(pyrene-1-yl)-9-fluorene-7-yl)pyrene in place of BTBANwas used as the host material. The device was tested by passing electriccurrent, a blue light emission with a current efficiency of 7.6 cd/A andan emission luminance of 760 cd/m² (maximum light emission wavelength:469 nm) was observed at a voltage of 6.5 V and a current density of 10mA/cm2. It was continuously tested by passing electric current at aninitial luminance of 500 cd/m², the half lifetime was founded to be18,000 hours or more.

Example 6

The organic EL device was fabricated similarly as Example 2 except that1-(4-(naphthalene-1-yl)phenyl)-6-(naphthalene-2-yl)pyrene in place ofBTBAN was used as the host material. The device was tested by passingelectric current, a blue light emission with a current efficiency of 7.8cd/A and an emission luminance of 780 cd/m² (maximum light emissionwavelength: 469 nm) was observed at a voltage of 6.5 V and a currentdensity of 10 mA/cm2. It was continuously tested by passing electriccurrent at an initial luminance of 500 cd/m², the half lifetime wasfounded to be 19,000 hours or more.

Comparative Example 1

The organic EL device was fabricated similarly as Example 1 except that6,12-bis(diphenylamino) chrysene in place of Compound (D-1) was used asthe doping material. The device was tested by passing electric current,a blue light emission with a current efficiency of 3.1 cd/A and anemission luminance of 311 cd/m² (maximum light emission wavelength: 451nm) was observed at a voltage of 6.2 V and a current density of 10mA/cm². It was continuously tested by passing electric current at aninitial luminance of 500 cd/m², the short half lifetime was founded tobe 1,000 hours.

Comparative Example 2

The organic EL device was fabricated similarly as Example 1 except that6,12-bis(4-isopropylphenyl-p-tolylamino) chrysene in place of Compound(D-1) was used as the doping material. The device was tested by passingelectric current, a blue light emission with a current efficiency of 5.9cd/A and an emission luminance of 594 cd/m² (maximum light emissionwavelength: 462 nm) was observed at a voltage of 6.3 V and a currentdensity of 10 mA/cm². It was continuously tested by passing electriccurrent at an initial luminance of 500 cd/m², the short half lifetimewas founded to be 4,590 hours. According to the above results, it wasshown that the organic EL devices on Examples 1 to 6 have longerlifetimes than those of the organic EL devices of Comparative Examples 1and 2 since two or more of substituent bonded to the terminal benzenerings of the doping materials prevent from the association betweenCompounds in the organic EL devices.

INDUSTRIAL APPLICABILITY

As explained above in details, the organic EL device employing thearomatic amine derivatives of the present invention exhibits adequateluminance of emitted light at low driving voltage and high currentefficiency, and has a long lifetime due to its difficult deteriorationduring a long time use. Therefore, it can be useful for applying it to aflat light emitter of a flat panel display for a television hanging onwalls, a backlight for a display and the like.

1. An aromatic amine derivative is selected from the group consistingof:


2. The aromatic amine derivative according to claim 1, wherein thearomatic amine derivative is a compound of formula D-1.
 3. The aromaticamine derivative according to claim 1, wherein the aromatic aminederivative is a compound of formula D-2.
 4. The aromatic aminederivative according to claim 1, wherein the aromatic amine derivativeis a compound of formula D-5.
 5. The aromatic amine derivative accordingto claim 1, wherein the aromatic amine derivative is a compound offormula D-6.
 6. The aromatic amine derivative according to claim 1,wherein the aromatic amine derivative is a compound of formula D-9. 7.The aromatic amine derivative according to claim 1, wherein the aromaticamine derivative is a compound of formula D-17.
 8. The aromatic aminederivative according to claim 1, wherein the aromatic amine derivativeis a compound of formula D-18.
 9. The aromatic amine derivativeaccording to claim 1, wherein the aromatic amine derivative is acompound of formula D-20.
 10. The aromatic amine derivative according toclaim 1, wherein the aromatic amine derivative is a compound of formulaD-21.
 11. The aromatic amine derivative according to claim 1, whereinthe aromatic amine derivative is a compound of formula D-22.
 12. Thearomatic amine derivative according to claim 1, wherein the aromaticamine derivative is a compound of formula D-23.
 13. The aromatic aminederivative according to claim 1, wherein the aromatic amine derivativeis a compound of formula D-25.
 14. The aromatic amine derivativeaccording to claim 1, wherein the aromatic amine derivative is acompound of formula D-26.
 15. An organic electroluminescence devicecomprising an aromatic amine derivative according to claim
 1. 16. Theorganic electroluminescence device according to claim 15, wherein thearomatic amine derivative is a doping material.